Method of making a valve poppet construction



Oct. 26, 1965 E. E. PRATHER ETAL 3,213,524

METHOD OF MAKING A VALVE POPPET CONSTRUCTION Original Filed Sept. 12,1958 I )Z @ZA fla 4M agg United States Patent 3,213,524 NIETHOD OFMAKING A VALVE POPPET CONSTRUCTIGN Edwin E. Prather and Gunther Pfeifer,South Bend, Ind., and Craig E. Hamhidge, Alpena, Mich., assignors to TheBendix Corporation, South Bend, Ind., a corporation of DelawareContinuation of application Ser. No. 760,695, Sept. 12, 1958. Thisapplication Sept. 21, 1962, Ser. No. 225,421

1 Claim. (Cl. 29-157.1)

This is a continuation of our prior application No. 760,695 filedSeptember 12, 1958, now abandoned.

The present invention relates to a method of producing valve poppets,and more particularly to a valve poppet and/ or a method of producingthe same which does not require machining of any kind.

A further object of the present invention is the provision of a new andimproved method of making a valve poppet in which the poppet is mouldedin such a way that no flash will be produced on the surface whichsupports the washer of resilient valve seat engaging material.

A still further object of the present invention is the provision of anew and improved method of making a valve poppet in which there is afirst poppet body section having a fiat end face, a second poppet bodysection having a flat end face, and a washer of resilient valve seatengaging material sandwiched between the flat end faces of the poppetsections, and which poppet sections are held together by a projectingboss on one of the sections which extends into a recess of correspondingconfiguration in the other of the poppet sections, and which boss islocked in place by an annular ridge located either on the side surfacesof the boss or recess when it is positioned in an annular groove in theother of the side surfaces of the boss or recess.

, A still further object of the present invention is the provision of anew and improved method of making a valve poppet in which the ridge thatis formed on the sidewalls of either the boss or recess is provided withan interference fit with respect to the sidewalls of the other of theboss or recess, and the body sections containing the boss and recessrespectively are formed from a material sufliciently resilient as topermit the body section to deform sufiiciently to receive the ridge whenthe boss and recess are telescoped together, and thereafter returnsubstantially to their initial shape when the ridge reaches the annulargroove to lock the sections together.

The invention resides in certain constructions and arrangements andmethods of producing the same; and further objects and advantages willbecome apparent to those skilled in the art to which the inventionrelates from the following description of several preferred embodimentsand methods of producing the same described with reference to theaccompanying drawing forming a part of this specification, and in which:

FIGURE 1 is a cross sectional view of one embodiment of the invention,certain details of which are shown in exaggerated form to better depictits construction;

FIGURE 2 is a cross sectional view similar to FIGURE 1 but showinganother embodiment of the invention;

FIGURE 3 is a cross sectional view of the parts of the embodiment shownin FIGURE 2 but in disassebled form prior to their assembly; and

FIGURE 4 is a cross sectional view similar to FIG- URE 2 but showingstill another embodiment of the invention.

As previously indicated, the present invention relates to a type ofpoppet construction and/or method of making the same in which a strip ofresilient valve seat engaging material is clamped between two sectionsof a poppet 3,213,524 Patented Oct. 26, 1965 body which are snappedtogether. The construction contemplated utilizes a washer of valve seatengaging material having an opening therethrough through which a portionof the poppet member extends and which poppet member provides a pair ofopposing shoulders or faces to confine and hold the portion of thewasher surrounding its central opening. Poppet constructions havingopposing shoulders which hold the valve facing material can, of course,be machined from a solid piece of material; and could, of course, bemoulded by a single set of dies where the dies were made to separateupon the place passing through the longitudinal centerline A of thepoppet. Were such to be done, however, production methods would producea flash which would extend across the face 12 of the poppet upon whichthe resilient facing material is seated so that good valve seating couldnot be had without machining the flash away from the finished mouldedproduct.

In order that the valve poppet might be mounded on a mass productionbasis without producing a flash across the face 12 of the poppet bodybehind the resilient valve seat engaging material, the present inventioncontemplates forming the poppet body in two sections 10 and 20respectively which are snapped together toprovide smooth opposingshoulder surfaces which securely hold the seat engaging material 14 inplace. In the preferred method of making the valve poppet shown inFIGURE 1, the poppet section 10 is provided with a generally flat endsurface 12 for supporting the strip 14 (in this case a washer) of aresilient valve seat engaging material such as rubber. The section 10 isformed in a pair of separating die means which separate upon a plane Bthat is parallel and may be co-extensive with the end surface or facing12. Assuming that the poppet section 10 is cast in the position shown inthe drawing, the upper separable die member which forms the face 12 ofthe poppet section 10 will contain a cylindrical recess therein, thesidewalls of which are provided with an annular projection so as toprovide an annular recess 16 in the sidewalls of the boss 18 whichprojects from and is formed as an integral part of the lower poppetsection 10. In order that the solidified boss 18 can be removed fromsuch a die cavity, it will be necessary that a moulding material be usedwhich is sufficiently resilient to permit the boss 18 to deform and flowaround the portion of the die which forms the recess 16 as the boss iswithdrawn from its die cavity. Numerous plastic materials have thisproperty; and nylon is presently being used in the commercial productionof poppets embodying the principles of the present invention. Themaximum depth of groove 16 which can be moulded in this fashion, will ofcourse, depend upon the moulding material being used, and in the case ofthe nylon parts now being manufactured, a recess depth of approximately.005 of an inch is being used.

The upper section 20 of the poppet body shown in FIG- URE 1 may beformed in a generally similar manner by a pair of separating dies whichseparate upon the plane C, and the lower die portion of which willcontain a boss which projects upwardly into the cavity of the upper diemember, and which boss will contain an annular groove therein so as toform the annular ridge 22 in the finished moulded section 20. Themoulding material for the upper part 20 must have similar properties tothat used for the lower poppet section 10 so that the ridge 22 can bewithdrawn from its die with the ridge 22 intact upon the sidewalls 24 ofthe hole 26 that is formed within the upper poppet section 20.

The manufacture of the poppet shown in FIGURE 1 is completed by snappingthe upper poppet section 20 upon the stem or boss 18 of the lower poppetsection 10 with the annular washer of valve seating material 14positioned about the stem 18 and sandwiched between the surface 12 ofthe lower poppet section and the end surface 28 of the upper poppetsection 20. During the pressing operation of the section 20 onto thesection 10, each yields sufilciently to permit the ridge 22 to slideover the end of the boss 18 until it reaches the recess 16 of the lowerpoppet section 10, whereupon the two poppet sections 10 and 20substantially resume their shapes as originally cast so that the poppetsection 20 becomes locked upon the poppet section 10.

The valve poppet embodiment shown in FIGURE 2 is similar in manyrespects to that shown in FIGURE 1; and those parts in FIGURE 2 whichare similar to those shown in FIGURE 1 will be designated by a likereference numeral characterized further in that a prime mark is affixedthereto. One of the differences between the two embodiments is that thehole 26' in the embodiment shown in FIGURE 2 is formed in the lowerpoppet section 10' while the stem 18' is formed integrally with the toppoppet section 20'. Another significant difference is that the ridge 22is formed integrally on the stem portion 18' while its receiving groove16' is formed in the sidewalls of the hole 26'. A further significantdifference is that the ridge 22' is formed on the very end of the stemportion 18' instead of at a position intermediate its ends, as was donein the embodiment shown in FIGURE 1; and a still further significantdifference is that the stem portion 18' in the embodiment shown inFIGURE 2 is accurately formed of predetermined length and the hold 26 isaccurately formed of a predetermined depth, so that when the end of thestern portion 18' engages the inner end of the hole 26', the surface 28'of the poppet member 20' will be accurately positioned a predetermineddistance from the end face 12' of the lower poppet section 19'.

It is intended that the sections of the poppet shown. in FIGURE 2 may bemoulded in a manner similar to that recited for the embodiment shown inFIGURE 1. The separable die portions forming the lower poppet section1.0 may separate from its upper die portion on the imaginary plane Bcoincident with the face 12, and the upper portion of the die wouldcontain a boss which projects into a cavity in the lower portion of thediewhich boss would include a ridge corresponding in shape to the ridge16'. The poppet section 20' may similarly be moulded by a pair ofseparable die means which separate upon the plane C. The bottom portionof its die-forming means would contain a recess corresponding in shapeto the stem or boss 18 and would include a groove 22' in its sidewallsat its inner end; and its upper die portion would contain a cavitycorresponding in shape to the mushroomlike shaped head of the bodysection 20. A resilient yielding of the ridge 16 is likewise required inorder to extract the poppet portion 20' from its die forming means; aswill the poppet section 10 in order to withdraw the portion of the diewhich forms the recess 22'. The poppet shown in FIGURE 2 is assembled bypressing the poppet section 20 into the poppet section 10' with anannular washer of synthetic rubber 14 positioned therebetween, until thelower end of the stem 18' engages the bottom surface of the hole 26' toposition the surface 28' accurately with respect to the surface 12', andin which position the ridge 16' locks into the recess 22'.

Where the poppet members are to be assembled by hand, it will usually bedesirable to insert the stem 18 or 13' through the central opening ofthe facing material 14 or 14', and thereafter insert the stem 18 or 18'into the hole 26 or 26'. The poppet sections 10 and 20, or 10' and 20 asthe case may be, can thereafter be forced together until the lockingaction previously recited is achieved. Where the poppet sections shownin FIGURE 2 are to be assembled by machine on a mass production basis,however, it may be desirable to provide a fixture which will hold thepoppet members 10' and 20' aligned in axial relationship, position thefacing material 14 upon the face 12' and thereafter force the section 20toward the poppet portions 10' to cause the stem portion 18' to beforced through the central opening of the facing material 14 and theninto the hole 26 until the sections 10' and 20 become locked together.Similarly if the embodiment shown in FIGURE 1 were to be assembled on amass production basis using a similar arrangement, the poppet portion 20might be held by a suitable fixture, the facing material 14 would beplaced over the poppet portion 20 with its central opening aligned withthe hole 26, and thereafter the stem 18 of the poppet section 10 wouldbe forced through the hole of the facing material 14 into the hole 26 ofthe poppet section 20 in a single pressing operation.

The embodiment shown in FIGURE 4 is generally similar to that shown inFIGURE 2 excepting that each of the side surfaces of the recess 26" andthe boss 18" are provided with annular ridges for locking the sections20 and 10 together. Those portions which are similar to FIGURE 2 will bedesignated by a like reference numeral characterized further in that adouble prime mark is afiixed thereto. In some instances the boss 18" maybe provided with a diameter which generally corresponds to the openingprovided by the ridge 30 in the recess 26" so that only the ridge 16" ofthe boss 18 will have an interference fit with respect to the ridge 30.In other instances where a more firm locking action is desired, the boss18" may be provided with a diameter substantially equal to that of therecess 26" so that its ridge 16" will have an interference fit withrespect to the sidewalls of the opening 26 as well as with the ridge 30.Under such conditions when the boss 18 is pressed into the recess 26" avery substantial interference or locking action will be provided; andunder such conditions, it will be necessary that each of the sections 10and 20 is provided with suificient strength to withstand the necessarydeformation encountered during assembly of the parts.

It will be seen that all of the embodiments shown in the drawing providea locking action which is accomplished by means of a pair of opposingand engaging surfaces on the respective sidewalls of a boss and itsreceiving recess, one of which surfaces faces generally axially inwardlytowards the inner end of the recess while the other of the surfacesfaces generally axially outwardly of the recess to prevent separation ofthe sections once they engage each other. For the purposes of thefollowing claims, it is intended that the inner end of the recess 26"inwardly of the projection 30 might be thought of as a recess in thesidewalls of the recess 26" for the reception of the annular projectionor ridge 16" on the boss 18".

It will be apparent that the objects heretofore enumerated as well asothers have been achieved and that there has been provided a new andimproved poppet structure and/ or method of producing the same whereby apoppet can be made cheaply and if desired without a finished machiningoperation.

While several embodiments of the invention have been shown and describedin considerable detail, we do not wish to be limited to the particularconstructions shown and described; and it is our intention hereby tocover all novel adaptations, modification and arrangements thereof whichcome within the practice of those skilled in the art to which theinvention relates.

We claim:

An inexpensive method of manufacturing a valve pop:

ber having a projecting boss of generally uniform.

cross section extending into said cavity at a right angle to saidseparating plane, and said boss having a slight annular ridge adjacentits end;

solidifying a plastic material in said cavity provided by said diemembers to form a first plastic body with a hole therein the sidewallsof which contain an annular recess, said plastic material being of atype which will plastically deform sufliciently to permit said annularridge of said boss to be withdrawn out of the solidfied material whichthereafter substantially returns to its shape as solidified;

pulling the solidified material from the third and fourth die memberswith the ridge intact on its boss;

providing an annular washer of resilient material having an areagenerally corresponding to the largest flat face of said first andsecond plastic bodies and a central opening corresponding generally incross pulling said solidified material from said first and second diemembers and withdrawing said boss from said solidified material;

providing third and fourth die members which sepa- 10 rate upon a planeand which together form a cavity having a generally flat end facegenerally parallel to said separating plane and of different area thanthat of the fiat face of said first and second die members, and whichprovide a cavity section extending into one of the die members at rightangles to References Cited by the Examiner UNITED STATES PATENTS saidseparating plane of a cross section correspond- 2,142,438 1/39 Faiveley29-453 ing to that of said boss, said cavity section having an 2,194,9613/40 Walker 251357 X annular groove in its sidewalls generallycorrespond- 2,855,206 10/58 Haviland.

ing in shape to the ridge on said boss but spaced at 2,861,849 11/58Case.

generally predetermined greater distance from said 2,889,089 6/59Herrick et al.

flat face of said third and fourth die members when 2,952,439 9/60 Koons251-357 assembled than the ridge of said boss is spaced from 2,987,8126/ 61 Donaldson 29-453 the fiat end face of said first and second diemem- 3,013,308 12/61 Armour 29451 bers when assembled; 3,053,502 9/62Brooks 251-357 solidfying plastic material having the above specifiedproperties in the cavity of said third and fourth die members to form asecond plastic body having a boss with a ridge therein;

WHITMORE A. WILTZ, Primary Examiner. LAVERNE D. GEIGER, Examiner.

